Potential SAF demand scenarios in 2040 vs. current projected SAF pipeline capacity, by status and technology FIGURE 13 Note: 1. Bar chart shows proportions of different SAF technologies in the current project pipeline. Under the “realistic case” predicted by BNEF – in which roughly half of this pipeline (22.9 Mt) may become operational – the technology breakdown may not be scaled back proportionately, both because of HEFA-scalability constraints due to used cooking oil availability and because non-HEFA pathways face bigger technology deployment challenges. Sources: HSBC analysis for Global Aviation Sustainability Outlook and BNEF.Operational Construction Pre-FID Planned Under consideration Pipeline by status: HEFA Alcohol-to-jet Methanol-to-jet Gas-to-liquids Other Power -to-liquids Pipeline by technology:BNEF r ealistic case 5.7 MtReduced scenarioBase scenarioMomentum scenario 0 10 20 30 40 50 60 70Pipeline by status Pipeline by technology1Current projected SAF pipeline capacityFutur e SAF demand scenarios, 2040 Million tonnes, Mt The existing SAF pipeline is dominated by HEFA. If all the projects in the pipeline were to progress to construction and operation, HEFA capacity could reach ~30 million tonnes soon after 2030. However, estimates of the future supply of used cooking oil (UCO) – a key feedstock for HEFA – suggest that this production pathway may face constraints. A bottom-up calculation based on UCO availability and collection rates suggests that production of just 8.6 million tonnes per year of HEFA by 2040 would be more realistic.206 Constraints on UCO could arise from various factors. For example, geographic concentration of UCO in selected markets can affect feedstock flows and, consequently, the ability of projects to secure the inputs needed for SAF production (see Chapter 3.6). In addition, competition with renewable diesel production can divert UCO supply away from the aviation industry and reduce the pipeline further.This future tightening of UCO supply and its impact on the growth of HEFA, plus volatile market conditions increase the urgency for additional, technologically diverse SAF plants to meet potential demand by 2040. Improvement in UCO collection and rapid diversification by SAF producers into other feedstocks, where allowed by regulation, could ease some of the constraints. However, the production of SAF from alternative waste or byproduct inputs will require the commercial expansion of more expensive alcohol-to-jet (AtJ) and gasification Fischer-Tropsch (GFT) fuel pathways. Feedstock restrictions in selected regions may also need to evolve to recognise the need for a greater pool of raw materials where the impact on emissions and land use are positive. Technology considerations Global Aviation Sustainability Outlook 2026 54